BmAbl1 Regulates Silk Protein Synthesis via Glutathione Metabolism in Bombyx mori

Abstract

Bombyx mori, domesticated from wild silkworms, is an economic insect that feeds on mulberry leaves and produces silk. In the current study, we demonstrated the contribution of BmAbl1 in silk protein synthesis. The inhibition and knockout of BmAbl1 can reduce the larva weight and CSW. The effect on CSW of BmAbl1 is not on the transcriptional level, but on the translational level. RNA-sequencing data suggested that amino acid synthesis and the metabolism process had a great difference between the BmAbl1- and Control strain, particularly glutathione metabolism. An abnormality in glutathione metabolism led to the reduction of free glycine and serine content, which are the main components of fibroin protein. Finally, fibroin protein synthesis has been reduced, including fibroin-heavy chain, fibroin-light chain, and p25 protein. This finding brought to light the role of BmAbl1 in the silk protein synthesis process.

Advances in the extracellular signal‐regulated kinase signaling pathway in silkworms, Bombyx mori (Lepidoptera)

“…In silkworms, the proliferation of silk gland tissue resembles tumors. Raf‐regulated MAPK activation affected the synthesis of silk fiber protein and enhanced silk production in silkworm cocoons (Ma et al, 2018; Qin et al, 2022), suggesting that Raf‐regulated signaling pathways made an important contribution to the enhancement of silk production in silkworm cocoons. However, under certain pathological conditions, C‐Raf can be activated by MEK independent of Ras, such as when overexpression of C‐Raf and MEK or downregulation of kinase inhibitor protein (RKIP) and Mst2 resulted in enhanced interaction between C‐Raf and MEK (Leicht et al, 2013).…”